P. J. Costa Branco

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Biomedical engineering applications of ionic polymer-metal composites like motion devices for endoscopy, pumps, valves, catheter navigation mechanisms and espinal pressure sensors makes it important to properly model IPMCs for engineering design. Particularly, IPMC continuum models and their electric equivalent circuit representation are critical to a more(More)
Fish are particularly sensitive to connectivity loss as their ability to reach spawning grounds is seriously affected. The most common way to circumvent a barrier to longitudinal connectivity, and to mitigate its impacts, is to implement a fish passage device. However, these structures are often non-effective for species with different morphological and(More)
Longitudinal connectivity is considered a key issue in river management, as it shapes ecological processes from single organisms to populations and ecosystems. Recently, it was shown that network analysis based on spatial graphs has promising applications as a tool for the assessment of connectivity in riverine systems. In this study we used a graph theory(More)
This paper studies two important questions related with switched reluctance machines: 1. In what conditions we can consider to use the SRM linear model but with sufficient accuracy to predict its steady-state characteristics? 2. To take or not to take into account the mutual inductances in the 6/4 SR non-linear model? Are there any significant errors when(More)
Unimorph design consisting of a piezoceramic bonded to an elastic surface is the most common structure used to induce deformations. The analytic models developed by Park and Agrawal are extensively used to determine the induced strain on piezo-actuated surfaces. These models are based on different strain distribution hypothesis that, however, do not(More)
The disruption of longitudinal connectivity caused by artificial barriers in rivers is considered to be a major threat to freshwater fish communities at the global scale. In Portugal, the construction of several big dams all through the 20th century was a major cause of disappearance or decline of long distance migratory fish species from various rivers. In(More)
Dams and weirs strongly affect or interrupt the longitudinal connectivity of rivers, by limiting the movements of several fish species while altering and fragmenting habitats. Fishways, especially pool-type fishways, are used to diminish this impact by enabling fish to negotiate barriers. The aim of this work is to study the behaviour of a small-sized(More)
Background. Worldwide predictions suggest that up to 75% of the freshwater fish species occurring in rivers with reduced discharge could be extinct by 2070 due to the combined effect of climate change and water abstraction. The Mediterranean region is considered to be a hotspot of freshwater fish diversity but also one of the regions where the effects of(More)
Climate change will predictably change hydrological patterns and processes at the catchment scale, with impacts on habitat conditions for fish. The main goal of this study is to assess how shifts in fish habitat favourability under climate change scenarios are affected by hydrological stressors. The interplay between climate and hydrological stressors has(More)